Pneumatic actuating unit.



A. G. GULBRANSEN.

PNEUMATIC AOTUATING UNIT.

APPLICATION FILED MAR. 20,1909,

Patented Dec. 21, 1909.

Ivww/fw. M qquLa/m nae/v UNITED AXEL G. GULBRANSEN.

OF CHICAGO, ILLINOIS, ASSIGNOB TO GULBBANSEN 6k DICKIN- SON COHPANY, OFCHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

PNEUMATIC ACTUA'IING UNIT.

Specification 0! Letters Patent.

Patented Dec. 21, 1909.

Application tiled latch 20, 1909. Serial No. 454,834.

To all whom it may concern:

llc it known that I, Axon. (l. GrrLnaANsnx, a citizen of the [hatedStates, residing at Chicago. in the county of Cook and State ofIllinois. have invented a certain new and useful improvement inPneumatic Actuating Units for Use in Pneuniatically-O eratcd Pianos, ofwhich the following is a all, clear. concise. and exact description,reference being had to the accompanying drawings. forming a part of thisspecification.

My invention relates to pneumatic actuating units for use inpneumatically operated pianos aml its object is to provide improvedconstruction and arrzmgenu-ut, particularly of the primary valve.mechanism.

In pneumatic actuating units the primary valve is operated rn )idly andsuddenly and should have. thereiore. great freedom of movement. Theseats for the valve should be rigid and Secure and should be constructedto insure good engagement and to prevent leakage. The construction andarrangement should also be such that the engagementbctween the valve andits seats is noiseless. All these various desirable fea- (tlleH areobtained by any construction and arrangement. which is clearly shown inthe au'com muying drawing. in which Figure I is a top view of apneumatic actuating unit: Fig. 2 is a section view taken on plane 2-2.Fig. 1; Fig. 3 is a section view taken through the valve on plane 3-3,Fig. 2; Fig. 4 is an underside view of the valve. parts being brokenaway; and Fig. 5 is a to view of a ring forming a seat for the va ve.

The actuating unit frame comprises the main supporting block 1 and thevalve block :2 mounted on the main block and removably secured theretoas by means of screws 3. llinged at the left lower edge of block 1 isthe movable member or plate 4 having at. its right end an extension orshelf 5 for engaging directly or through connecting mechanism with theabstract rods 0| striking mechanism of the-piano. (lined about the edgesof the block I and )lttlt 4 is flexible fabric (5. which with said blockand plate forms a bellows chamber 7. The block I is recessed from thetop to form the upper and lower diuphru m chalulx-rs 8 and 9. so mrutedby the diap u'aglu 10. lliugcd at he left. end of the. upper diaphragmchamber and extending diametrically across said chamber and over thediaphragm is a lever 11 secured at an intermcdnlte point; to the centerof the diaphragm by means of a felt disk 12.

Into the valve block 2 is cut the cylindrical valve chamber 13 whose u)per end is covered by the annular metallic seat 14 cashioned by aleather washer 15, the opening 16 communicating with the atmosphere. Thelower wall 17 of the valve chamber has the central owning l8 connectingthe valve chambenwitll the upper diaphragm chamber. The sides of thisopeniu taper downwardly the entire distance and are lined by a n'letalring 19 correspondingly tapered and whose upper edge is finished to forma smooth annular valve seat. The ring is glued in the opening andthc'tapercd arrange. ment assists in rigidly and securely holdmg the rinin place and also prevents the ring from alling into the diapln-a uchamber. should it ever become loosene This arrangement also causes theseat ring 19 to he conumnsating as should for an reason the opening 18become larger and t e ring ltKI:-icned as by contraction of the block 2,the valve 20 which is under ahnosphcric pressure will force the ringdownwardly into firm and close engagement with the opening, thusmaintaining at all times a perfectfit between the ring and the opening.

'ithin the valve chamber is the cylindrical valve 20, whose detailconstruction is shown in Figs. 3 and 4. The main member is a wooden disk21 having the annular flange 22 extending downwardly from its cd e. Adiaphragm or disk 23 of air tight faliric. such as rubber. is glued atits edge to the end face of the flange and said disk is reinforced Irv adiaphragm or disk :24 glued thereto at its edge. said disk it beingpreferably of leather. 'ithin the compurtnn'ntformed by the flange andthe disks 2i and '33. some soft cushioning material is placed and thismay he in the form of a felt disk inserted before the rubber disk 23 isapplied to the flange. The upper end of seat rin I ill extends a shortdistance allure the wul l7 and the valve is nornudly seated thereon. theinner diameter of the flange being gl't'ttltl than that of the ring andthe outer diameter of the disk Ll being sulliciently less than thelinnu-ter of the valve chamber to allow perfect freedom of operation ofthe valve. Glued at its a per end to the center of the leather disk 2418 the valve stem 26, which extends downwardly through opening 18 andinto the upper dia hragm chamber, its lower end being secure to theright end of lever 11 by means of a felt disk 27.

The left ends of blocks 1 and 2 are in vertical register and are securedto the wall 28 of a vacuum chamber frame 29, a washer 30 of leatherbeing interposed. A passageway 31 connects the 11 per diaphragm chamberwith the vacuum cliamber and a passageway 32 connects the lowerdiaphragm chamber with the vacuum chamber, this connection, however.bein throttled by the small opening 33 through disk 34 applied over theend of said passageway. T 1e passageway 32 also connects via passageway35 with a conductor 36 leading to an opening in the tracker board overwhich the music sheet travels, this tracker board not being shown. Apassageway 37 connects the valve chamber with the bellows compartment 7.

W hen the tracker board openings are closed, both diaphragm chambersconnect with the vacuum cl1a1nl)cr;-tlie diaphragm is down and the valveis held against the ring seat by atmospheric pressure. \Vhen a trackerboard opening is exposed by the sheet, air under atmospheric pressurerushes through passageun and 32 to blow up the diaphragm an: to raisethe valve, the diaphragm force bcing multiplied by the lever connectionbetween the diaphragm and valve which has already been described.'lluvalvc now closes atmosphere outlet 16 and allows the bellowscompartment to conncct with the vacuum chamber throw-ll opening 18 andpassageway 31. The pl ate 4 is therefore raised and the piano strikingmechanism having connection with the extcnsion 5, is actuated. When thetracker hoard opening is a ain closed, the pressures in the diuphra clambers equalize through opening 33 nor the valve returns to its lowerscat to disconnect the bellows chamber from the vacuum chamber and toreconnect the hollows chamber with atmosphere, whereupon plate 4 dropsand the striking mechanism is rrlcascd. 'lhc upward throw of the plate Iis cushioned by a pad 38 which strikes the abutment screw 39. thisabutment screw also allowing adjustment of the actuation of the strikingmechanism by the plate l.

True and accurate engagement of the valve with its seats is alwaysassurct'l on account ol the flexible felt connection mtwcrn the stem andlover, and the flexible connection ol' the stem with the leather disk ordiaphragm 24. 'lhosc connections allow the valve to move freely andpractically indopomh-ntly of the lever 11. The cushioning material 25absorbs all shocks and softens the en 'ugcment of the valve with itsseats. The ru ibcr disk 23 prevents leakage of air through opening 18when the valve seats on ring 19. The opening 18 bcii v tapered thronhout its length, the taper-t seat ring 19 wifi at all times be held withperfect fit in the opening by the valve pressing against the ring.

The result of the various features described above is to produce veryefficient and noiseles operation.

As changes both in construction and or rangemcnt could be made withoutdeparting from the s irit of my invention, 1 do not. limit; myse f tothe exact construction and operation shown, and I desire to secure thefollowing claims by Letters Patent:

1. In a pneunnitic actuating device of the class described, thecombination with a valve having an opening and a diaphragm secured oversaid opening, of a seat for engaging said diaphragm within the edge ofsaid opening.

In a pneumatic actuating device of the class described, the combinationof a frame forming a valve chamber, a valve in said chamber having acavity and a diaphragm secured over said cavity, a diaphragm tlllllllbcrbelow the valve clulmlu-r, a diaphragm in said chamber, a valve stemhaving coma-ction at one end with the diaphragm in said diaphragmchamber and at its other cud being connected with the valve diaphragm,and a passagcwav controlled by said valvr.

3. In a pneumatic actuating device of the class descrlbcd, thecombination with a valve comprising a disk having a cavity, cushioning;material filling the cavity, and a diaphragm closing the cavity, of aframe forming a valve chamber for said valve, a stem secured to thediaphragm and extending therefrom, actuating mechanism for said valveconnected with said stem, and a passageway controlled by said valve.

4. In a pneumatic actuating device of the class described, thecombination with a valve comprising adisk having a cavity, cushioningmaterial Ill said cavity, and a die hragm covering the cavit and sccurcdto t to disk, of a stem secure at one end to the diaphragm, actuatingmechanism having flexi- )ll' connection with the other end of said stcm,and a passageway controlled by said valve.

In a pneumatic actuating device of the class described, the combinationof a disk having a rim formin' a cavity with said disk, an air tight diuilu'a un secured to the rim over the cavity, a reinfdueing din Jhragmalso secured to the rim on to) of tie lirst mentioned din ihrugm, saiddisk and diaplu'u ms constituting a valve structure, a seat or saidvalve struutin-c, a. slum secured at. one cud to the reinforcingdiaphragm,

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lllt) and actuating mechanism having flexible connection with the otherend of said stem.

6. In a pneumatic actuating device of the class described. thecombination of a body part having a rim forming a cavity therewith, adiaphru m sccnrec to the run over the cavity, said isk and diaphragmconstitutiug a valve structure, and an annular valve seat for engagingwith the diaphragm within said rim.

7. In a pneumatic actuating device of the class described. thecombination of a body part having a rim formiu a cavity therewith, adiaphragm secure to the rim over the cavity, said disk and diaphragmconstitutiln a valve structure, an annular valve seat or engagin withthe diaphragm within said rim, a vfive stem secured to the diaphragm.and actuating mechanism having connection with said stem.

8. In a pneumatic actuating device of the class described, thecombination of a body part having a rim formin a cavity therewith, adiaphragm secure to the rim over the cavity, said disk and diaphragmconstituting a valve structure, an annular valve seat for engaging withthe diaphragm within said rim, a valve stem secured at one end to thediaphragm. and actuating mechanism having flexible connmztion with theother end of said stem.

9. In a pneumatic actuating device of the class dcscrila-d, thecombination of a rigid disk having a rim formi a cavity there with, aflexible disk secure to the rim over the cavity, cushioning material inthe cavity, said disks and material constituting avalve structure. andan annular valve seat for engaging with the flexible diaphragm withinthe rim.

10. in a pneumatic actuating device of the ('lllSS described. thecombination of a rigid circular valve disk having an annular flange onone face foru'iing a compartment therewith. a flexible disk secured tothe flange end and coveriu the compartment, and an annular seat. orengaging with said flexible disk, the diameter of said scat being lessthan the inner diameter of the flange.

11. in a pneumatic actuating device of the class described, thecombination of a rigid circular valve disk having an annular flange onone face forming a compartment therewith, a flexible disk secured to theflange end and covering the compartment, an annular seat for engaginwith said flexible disk, the diameter of said seat being less than theinner diameter of the flange, and cushioning material within thecompartment.

12. In a pneumatic actuating device of the class desicribed, theOOIlllJlllAtlUll of a rigid valve disk having a flange extending fromone face thereof and forming therewith a coinlpartment, an innerflexible disk scoured to tie flange end over the compartment, an outerflexible disk superposed on the inner flexible disk, and an annularvalve seat for enga iug the outer disk and having a diameter less thanthe inner diameter of the flange, said inner flexible disk beingiinpcrvious to air.

13. In a pneumatic actuating device of the class described, thecombination of a rigid valve disk having a flange extending from oneface thereof and forming therewith a compartment, cushioning materialwithin the com artment, an inner flexible disk secured to t to flan cend over the compartment, an outer flexible disk superposed on the innerflexible disk, and an annular valve seat for enga ing the outer disk andhaving a diameter lees than the inner diameter of the flange, said innerflexible disk being impervious to air.

in witness whereof I hereunto subscribe my name this 17th day of March.A. l). 1909.

Witnesses:

JULIA C. Looms, Wmnnmn L. Flsll.

